This glass barometer that forecasts the weather has been known to have been in operation since the beginning of the 17th century.
It works very simply.
In high pressure, i.e. on sunny days, the water level decreases towards the bottom.
In low pressure, when it is cloudy or raining, the level of the water increases.
When a Storm is imminent, it increases so much that it overflows.
Made from Cast Iron and glass.
Easy to use.